Osteogenesis imperfecta is a genetically and clinically heterogenous group of skeletal dysplasias characterized by bone fragility. Its severity ranges from nearly asymptomatic individuals to perinatal lethality. The majority of cases are caused by mutations in either the COL1A1 or the COL1A2 gene coding for alpha 1 and alpha 2 chains of collagen type 1, respectively, and a large number of pathogenic variants of these genes has been identified. We describe a novel COL1A1 mutation associated with prenatally diagnosed severe form of osteogenesis imperfecta...

PURPOSE OF REVIEW: This review highlights how skeletal dysplasias are diagnosed and how our understanding of some of these conditions has now translated to treatment options. RECENT FINDINGS: The use of multigene panels, using next-generation sequence technology, has improved our ability to quickly identify the genetic etiology, which can impact management. There are successes with the use of growth hormone in individuals with SHOX deficiencies, asfotase alfa in hypophosphatasia, and some promising data for c-type natriuretic peptide for those with achondroplasia...

Achondroplasia (ACH) is one of the most common short-limbed skeletal dysplasias caused by gain-of-function mutations in the fibroblast growth factor receptors 3 (FGFR3) gene. Distraction osteogenesis (DO) is a treatment option for short stature in ACH in some countries. Although the patients with ACH usually show faster healing in DO, details of the newly formed bone have not been examined. We have developed a mouse model of DO and analyzed new bone regenerates of the transgenic mice with ACH (Fgfr3(ach) mice) histologically and morphologically...

Osteogenesis imperfecta (OI) is a collagen-related disorder associated to dominant, recessive or X-linked transmission, mainly caused by mutations in type I collagen genes or in genes involved in type I collagen metabolism. Among the recessive forms, OI types VII, VIII, and IX are due to mutations in CRTAP, P3H1, and PPIB genes, respectively. They code for the three components of the endoplasmic reticulum complex that catalyzes 3-hydroxylation of type I collagen α1Pro986. Under-hydroxylation of this residue leads to collagen structural abnormalities and results in moderate to lethal OI phenotype, despite the exact molecular mechanisms are still not completely clear...

OBJECTIVE Chondrodysplasia punctata (CDP), a rare skeletal dysplasia, can lead to cervical spine instability and deformity. However, an optimal neurosurgical intervention has yet to be established. Thus, a retrospective study was conducted to assess the efficacy of various surgical interventions for children with CDP. METHODS The authors retrospectively reviewed 9 cases of CDP in which cervical decompression with or without posterior fusion was performed between April 2007 and May 2016. Patient demographics, preoperative clinical conditions, radiographic findings, surgical procedures, and the postoperative course were analyzed in detail...

The clinical management and decision-making in pregnancies in which there is suspicion of lethal fetal malformations during the prenatal period, such as lethal skeletal dysplasia (SD), demand a multidisciplinary approach coordinated by an experienced physician. Based on the presentation of a case of osteogenesis imperfecta type IIA, we offer and discuss recommendations with the intention of organizing clinical and laboratory investigations aiming toward the clinical management, prognosis, and etiological diagnosis of these malformations, as well as genetic counselling to patients who wish to become pregnant...

Researchers have identified a subset of Holstein having a range of skeletal deformities, including vertebral anomalies, referred to as complex vertebral malformation due to mutations in the SLC35A3 gene. Here, we report the first case in humans of SLC35A3-related vertebral anomalies. Our patient had prenatally diagnosed anomalous vertebrae, including butterfly, and hemivertebrae throughout the spine, as well as cleft palate, micrognathia, patent foramen ovale, patent ductus arteriosus, posterior embryotoxon, short limbs, camptodactyly, talipes valgus, rocker bottom feet, and facial dysmorphism including proptosis, nevus flammeus, and a cupped left ear...

Although mutations in ACAN, FGFR3, NPR2, and SHOX typically lead to skeletal dysplasia, and mutations in GHRHR, GH1, GHR, STAT5B, IGF1, IGFALS, and IGF1R usually underlie hormonal defects of the growth hormone (GH)-insulin-like growth factor 1 (IGF1) axis, such mutations have also been identified in patients with idiopathic short stature (ISS). Of these, SHOX abnormalities are known to account for a certain percentage of ISS cases, whereas the frequency of mutations in the other 10 genes in ISS cohorts remains unknown...

Skeletal dysplasias are a complex group of more than 350 disorders with phenotypic and genotypic heterogeneity affecting bone and cartilage growth. We studied a 2-year-old girl and her 21-year-old mother with disproportionate short stature. In addition to typical features of hypochondroplasia found in both patients, the child had deformities of the extremity bones, metaphyseal flares, and bilateral transverse (Bowdler) fibular spurs with overlying skin dimples detected at birth. Intravenous pamidronate was started in the child since the age of 17 days, and then every two months...

Patients with skeletal dysplasia frequently require surgery. This patient population has an increased risk for peri-operative complications related to the anatomy of their upper airway, abnormalities of tracheal-bronchial morphology and function; deformity of their chest wall; abnormal mobility of their upper cervical spine; and associated issues with general health and body habitus. Utilizing evidence analysis and expert opinion, this study aims to describe best practices regarding the peri-operative management of patients with skeletal dysplasia...

OBJECTIVES: This study aims to report rates of skeletal abnormalities and their risk factors in light of information obtained in a fetal autopsy series. PATIENTS AND METHODS: The study included 20 fetuses (11 males, 8 females and 1 ambiguous genitalia; mean age 19.3±4.0 weeks; range 16 to 32 week) who underwent autopsy in our hospital between January 2013 and March 2015. Fetuses were systematically classified according to age, gender, family history, abortus week, abortus type, and extremity and organ abnormalities...

The bony pelvis is constituted by the ilium, ischium, pubis, and sacrum. The pelvic radiograph is an important component of the skeletal survey performed in suspected skeletal dysplasia. Most of the common skeletal dysplasias have either minor or major radiological abnormalities; hence, knowledge of the normal radiological appearance of bony pelvis is vital for recognizing the early signs of various skeletal dysplasias. This article discusses many common and some uncommon radiological findings on pelvic radiographs along with the specific dysplasia in which they are seen; common differential diagnostic considerations are also discussed...

Mutations in the RMRP-gene, encoding the lncRNA component of the RNase MRP complex, are the origin of cartilage-hair hypoplasia. Cartilage-hair hypoplasia is associated with severe dwarfism caused by impaired skeletal development. However, it is not clear why mutations in RMRP RNA lead to skeletal dysplasia. Since chondrogenic differentiation of the growth plate is required for development of long bones, we hypothesized that RMRP RNA plays a pivotal role in chondrogenic differentiation. Expression of Rmrp RNA and RNase MRP protein subunits was detected in the murine growth plate and during the course of chondrogenic differentiation of ATDC5 cultures, where Rmrp RNA expression was found to be correlated with chondrocyte hypertrophy...

Multiple Epiphyseal Dysplasia (MED) is a relatively mild skeletal dysplasia characterized by mild short stature, joint pain, and early-onset osteoarthropathy. Dominantly inherited mutations in COMP, MATN3, COL9A1, COL9A2, and COL9A3, and recessively inherited mutations in SLC26A2, account for the molecular basis of disease in about 80-85% of the cases. In two families with recurrent MED of an unknown molecular basis, we used exome sequencing and candidate gene analysis to identify homozygosity for recessively inherited missense mutations in CANT1, which encodes calcium-activated nucleotidase 1...

BACKGROUND: Mutations in the COL2A1 gene cause type II collagenopathies characterized by skeletal dysplasia with a wide spectrum of phenotypic severity. Most COL2A1 mutations located in the triple-helical region, and the glycine to bulky amino acid substitutions (e.g., glycine to serine) in the Gly-X-Y repeat were identified frequently. However, the same COL2A1 mutations are associated with different phenotypes and the genotype-phenotype relationship is still poorly understood. Therefore, the studies of more patients about the recurrent mutations in COL2A1 will be needed for further research to provide more comprehensive clinical and genetic data...

BACKGROUND: Fibrous dysplasia (FD) is a rare benign bone disorder in which the normal bone is replaced by immature fibro-osseous tissue. However, some case reports have reported that FD showed significantly increased (99m)Tc-methylene diphosphonate ((99m)Tc-MDP) uptake on whole-body bone scintigraphy (WBS), which may mimic bone metastasis or skeletal involvement of the patients with known cancer. Thus, the purpose of present study is to observe the reliable characteristics and usefulness of single photon emission computed tomography/computed tomography (SPECT/CT) for the diagnosis of FD...

Cleidocranial dysplasia (CCD) is an autosomal dominant inheritable skeletal disorder characterized by cranial dysplasia, clavicle hypoplasia and dental abnormalities. This disease is mainly caused by heterozygous mutations in RUNX2, a gene that encodes an osteoblast-specific transcription factor. In the present study, mutational analyses of RUNX2 gene were performed on four unrelated Chinese patients with CCD. Four different RUNX2 mutations were detected in these patients, including one nonsense mutation (c...

INTRODUCTION: Achondroplasia is the most common skeletal dysplasia with a rate of nearly 1/10,000. The development of lower extremity deformity is well documented, and various modes of correction have been reported. There are no reports on the use of growth modulation to correct angular deformity in achondroplasia. METHODS: Medical Records from 1985 to 2015 were reviewed for the diagnosis of achondroplasia and growth modulation procedures. Patients who had been treated for angular deformity of the legs by growth modulation were identified...